Excel's number formatting system is a language of its own, and this question captures the friction that comes when you're fluent enough to want more but not quite fluent enough to make the syntax sing. The user already knows the two separate moves: display negatives as positive by providing a second format section, and suppress specific values like 20 and -20 using bracket conditions. The instinct to combine them is correct. The challenge is that Excel's format codes are sequential and positional, so you need to merge the logic into a single, coherent string that respects both the value-specific override and the general display rule.
The practical answer is a format code like `[=20]"";[=-20]"";#,##0;#,##0`. This tells Excel: if the value is exactly 20 or -20, show nothing; otherwise, apply the positive/positive display for all other numbers. The user's decimal problem stems from a missing trailing zero placeholder in their original code, not from the display logic itself. Adding the `#,##0` sections without decimals resolves that. The key insight is that Excel evaluates conditions before it applies general formatting, so you can stack the exceptions at the front and let the final sections handle the rest.
What this reveals is a deeper truth about working with spreadsheets: the tool is rarely the limit, but the interface between what you want and what you type can feel like a wall. The user is not asking for a macro or a script. They are asking for a more expressive format string, and that is a skill worth building. Once you understand that a format code is just a set of instructions evaluated in order, you stop seeing workarounds and start seeing a grammar for making the data look exactly how you need it to.
For anyone else staring at an axis that stubbornly shows values they do not want, or negatives that refuse to present as positives, the takeaway is this: learn the order of operations in format codes, and you unlock a quiet superpower. It is not glamorous. It will not make headlines. But it will save you time, frustration, and a few clicks through menus that never quite do what you mean. The user's question is a small, precise problem with a clear solution, and that is exactly the kind of problem worth solving properly.